Improving Voice Outcomes After Injury to the Recurrent Laryngeal Nerve

Abstract

Objectives: The present study aimed to determine the voice outcomes before and after the administration of voice therapy in patients who suffered an injury to the recurrent laryngeal nerve after undergoing thyroidectomy. Methods:The sample consisted of 26 patients (2 males and 24 females) aged between 18 and 80 years (m=55±12) who experienced injury to the recurrent laryngeal nerve following thyroidectomy that was used to treat a thyroid gland disease. Subjective and objective parameters of the voice of the patients as well as its aerodynamic aspects were assessed upon the completion of the surgical procedure and before and after the implementation of voice therapy. Objective voice analysis was performed with the help of computer software viz. "Speech Training for Windows, Version 4.00 -Dr. Speech "and" EZ Voice Plus (TM) v. 2.0;" while GRBAS scale was used for subjective voice assessment. The subjects were followed for two years. The data so collected during this period was analyzed by implementing descriptive statistical parameters, Chi-square test, t-test and Wilcoxon test. Results:Patients with an injury to the recurrent laryngeal nerve were found to have voice alterations in all vocal parameters of subjective voice assessment conducted using the GRBAS Scale. These alterations ranged from moderate to severe degree, which provided a high degree of roughness in the voice. Objective voice assessment parameter analysis showed a decrease in voice pitch, increase in shimmer, decrease in noise-to-harmonics ratio, decrease in maximum phonation time and a decrease in voiceless percentage. Overall, it was observed that there were significant differences in all parameters of subjective and objective voice assessment, before and after vocal therapy, except for variables regarding the noise-to-harmonics ratio and aerodynamic variable of the S/Z ratio, although, the results on these vocal parameters were better after voice therapy.

Voice Outcomes as a Results of Voice Therapy after Lobectomy and Thyroidectomy

“…Similar conclusions have already been reported by Žunić et al (2017), who observed a decrease in the noise-to-harmonic ratio (NHR) after voice nerve therapy in patients with recurrent laryngeal nerve injury ( 19 ). Cantarella et al (2010) also observed a decrease in the NHR three months after voice therapy in patients with vocal cord paralysis and concluded that the therapy was able to achieve minimal spontaneous glottal compensation ( 20 ).…”

Recurrent laryngeal nerve transection in mice results in translational upper airway dysfunction

“…Similarly, RLN transection impaired the frequency bandwidth of many call types at 1 WPS. These findings suggest that mice with unilateral VF paralysis lose the ability to modulate the frequency in their calls, similar to human patients who experience impairment in their phonation frequency (i.e., pitch range) following injury (Junuzovic‐Zunic, Ibrahimagic, Altumbabic, Umihanic, & Izic, ; Sridhara, Ashok, Raghunathan, & Mann, ; Xue, Mittal, Zheng, & Bielamowicz, ). Unilateral VF paralysis patients also demonstrate impaired maximum phonation times (Sridhara et al, ), which was observed in the current study as decreased call durations and durations of peak frequency in a collection of call types in RLN transected mice.…”